i8 utf8_len(u8 ch) { if (ch<128) return 1; if ((ch>>5)== 0b110) return 2; if ((ch>>4)== 0b1110) return 3; if ((ch>>3)==0b11110) return 4; return -1; } u32 utf8_p(u8* p) { i32 len = utf8_len(*p); switch (len) { default: UD; case -1: return (u32)-1; case 1: return *p; case 2: return (0b11111u&*p)<< 6 | (0b111111u&p[1]); case 3: return (0b1111u &*p)<<12 | (0b111111u&p[2]) | (0b111111u&p[1])<<6; case 4: return (0b111u &*p)<<18 | (0b111111u&p[3]) | (0b111111u&p[2])<<6 | (0b111111u&p[1])<<12; } } B fromUTF8(char* s, i64 len) { u64 sz = 0; i64 j = 0; while (true) { i8 l = utf8_len((u8)s[j]); if (l==-1) thrM("Invalid UTF-8"); if (j>=len) { if (j!=len) thrM("Invalid UTF-8"); break; } sz++; j+= l; } B r = m_c32arrv(sz); u32* rp = c32arr_ptr(r); u64 p = 0; // TODO verify for (i64 i = 0; i < len; i+= utf8_len((u8)s[i])) rp[p++] = utf8_p((u8*)s+i); // may read after end, eh return r; } B fromUTF8l(char* s) { return fromUTF8(s, strlen(s)); } void printUTF8(u32 c) { if (c<128) printf("%c", c); else if (c<=0x07FF) printf("%c%c" , 0xC0| c>>6 , 0x80| (c &0x3F) ); else if (c<=0xFFFF) printf("%c%c%c" , 0xE0| c>>12, 0x80| (c>>6 &0x3F), 0x80| (c &0x3F) ); else printf("%c%c%c%c", 0xF0| c>>18, 0x80| (c>>12 &0x3F), 0x80| (c>>6 &0x3F), 0x80| (c&0x3F)); } u64 snprintUTF8(char* p, u64 l, u32 c) { if (c<128) return snprintf(p, l, "%c", c); else if (c<=0x07FF) return snprintf(p, l, "%c%c" , 0xC0| c>>6 , 0x80| (c &0x3F) ); else if (c<=0xFFFF) return snprintf(p, l, "%c%c%c" , 0xE0| c>>12, 0x80| (c>>6 &0x3F), 0x80| (c &0x3F) ); else return snprintf(p, l, "%c%c%c%c", 0xF0| c>>18, 0x80| (c>>12 &0x3F), 0x80| (c>>6 &0x3F), 0x80| (c&0x3F)); }